[PR92854] Add 'libgomp.oacc-c-c++-common/pr92854-1.c'

... to document the status quo.

	libgomp/
	PR libgomp/92854
	* testsuite/libgomp.oacc-c-c++-common/pr92854-1.c: New file.

From-SVN: r279120

libgomp/ChangeLog

 2019-12-09  Thomas Schwinge  <thomas@codesourcery.com>
 
+	PR libgomp/92854
+	* testsuite/libgomp.oacc-c-c++-common/pr92854-1.c: New file.
+
 	* testsuite/libgomp.oacc-c-c++-common/host_data-6.c: New file.
 
 	* target.c (gomp_exit_data): Use 'gomp_remove_var'.

libgomp/testsuite/libgomp.oacc-c-c++-common/pr92854-1.c

+/* Verify that 'acc_unmap_data' unmaps even in presence of dynamic reference
+   counts.  */
+
+/* { dg-skip-if "" { *-*-* } { "*" } { "-DACC_MEM_SHARED=0" } } */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <openacc.h>
+
+int
+main ()
+{
+  const int N = 180;
+
+  char *h = (char *) malloc (N);
+  char *d = (char *) acc_malloc (N);
+  if (!d)
+    abort ();
+  acc_map_data (h, d, N);
+
+  char *d_ = (char *) acc_create (h + 3, N - 77);
+  assert (d_ == d + 3);
+
+  d_ = (char *) acc_create (h, N);
+  assert (d_ == d);
+
+  acc_unmap_data (h);
+  assert (!acc_is_present (h, N));
+
+  return 0;
+}